The present invention relates to automobile exterior components. In more detail, it relates to automobile exterior components prepared from a thermoplastic resin composition, having good balance between impact resistance and fluidity and being excellent in coating heat resistance and rigidity.
In recent years, a variety of plastic materials have been used for automobile exterior components such as outside sheathing panels, hub caps, spoilers and bumpers, and requirements for such plastic materials have been rising. For example, high-level impact resistance, fluidity and rigidity are required for plastic materials used for outside sheathing panels. These exterior components are, in many cases, subjected to urethane coating or melamine coating for improving their exterior appearance. Especially, in recent years, a melamine coating, which has been used for coating steel plates for automobile bodies, is also applied for coating outside sheathing resin plates and number of such cases is increasing. Since the baking temperatures in such melamine coating is relatively high, materials to be coated are required to have high heat resistance (coating heat resistance).
Blends composed of a polyamide resin which is excellent in chemical resistance, heat resistance, abrasion resistance and the like and an ABS resin which is excellent in impact resistance, moldability and the like, namely, polyamide/ABS alloys, is proposed (Japanese Patent Publication No. 38-23476. Hereinafter, "Japanese Patent Publication No." is abbreviated to "JP-B-".). Since the polyamide resin and the ABS resin, however, have poor compatibility, a method in which a modified copolymer prepared by copolymerizing an unsaturated carboxylic acid with styrene and acrylonitrile is compounded to these resins has been proposed (Japanese Patent Laid-Open Publication Nos. 63-179957 and 64-158). Hereinafter, "Japanese Patent Laid-Open Publication No." is abbreviated to "JP-A-".). However, these materials do not sufficiently attain the object of the present invention, namely good balance between impact resistance and fluidity and excellent coating heat resistance and rigidity.